Cervelo R3 SL Seatpost clamp breakages...

Been riding (or trying to) an R3 SL from Cervélo. So far I've broken two seatpost clamps. These clamps are scary light at 9grams each and are a lot different from the standard R3.

The French distributor tells me I'm the ONLY person ever to break one let alone two and Cervélo Canada very nicely sent me new ones but I don't feel I'm at the end of this saga.

So, anybody else out there having a similar issue? Yes, I did use a Torque Wrench and Yes, it has been calibrated and double checked against my LBS's same tool. The frame is a size 58 (does that matter?) and I weigh a miserly 70kg... my legs ressemble Chicken Legs Rasmussen and not Freddy Cancellera, so in theory, this shouldn't be happening and it is spoiling the experience of one FINE frame.

For the record, Cervélo Customer Service have been excellent but I can't believe I'm the only one...